Heat treating machine



Jan. 22, 1946. H. E. soMEs 2,393,434

HEAT TREATING MACHINE Filed Feb, 24, 1943 7 Sheets-Sheet 2.

INVENTOR Howard Soines ATTORNEY Jan. 22, 1946. H. E. SOMES HEAT TREATING MACHINE Filed Feb. 24, 1943 7 Sheets-Sheet 3 1- .3 E s, I 1 M 5 1 a a 1 9 9 2 u m o o O I 1. K W Q M 11 1 L 4 {u 9 Y w I 1 INVENTCR I 76 fldwardl'. Somes ATTORNEY Jan. 22, 1946. H. E, SOM S v 2,393,484

HEAT TREATING momma Filed Feb 24, 1943 Sheds-Sheet 5 INVENTOR .Hawardfil Solnes' A TTORNE Y I 7 Sheets-Sheet 6 ATTORNEY H0 ward Z, Somes Jan. 22, 1946. H. E. SOMES HEAT TREATING MACHINE '7 Sheets-Sheet 7 Filed Feb. 24, 1943 w h l/Wal I 'II'I IIIII I IIIIIIMIWN/dl n II IIIIIIIII IIII INVENTOR Howard E 50212 6 Immlllllllllh llll\\\\\\\\\\\ A w Zara/ally nmmmm UNITED STATES PATENT OFFICE HEAT TREATING MACHINE Howard E. Som'es, Detroit, Mich., nssignor to Budd Induction Heating, Inc., Philadelphia, Pa., a corporation of Michigan Application February 24, 1943, Serial No. 476,991

7 Claims. (Cl. 219-43) This invention relates to heat treating and more particularly to an improved machine for heat treating metallic articles.

In heat treating certain types of articles, particularly by electromagnetic induction heating and quenching, it is necessary to operate with close clearance between the article surface and such elements as, for example, the heating head, yet provision must be made for relative movecurately positioning the different parts relatively to each other, and positively holding them in predetermined relation during operation.

Heretofore, the satisfactory hardening by heating and quenching of surface areas on articles having faces of sinuous conformation 55 has been a diflicult if not impossible operation, and a further object is to provide a machine for hardening sinuous surfaces on metallic articles with such accuracy and precision as substantially eliminates variations in the product and permits quantity production of large numbers of items in each of which the depth and pattern of the hardened area is accurately controlled.

ment therebetween to permit easy and quick -These and other objects which will be apinsertion of a work piece in place and removal parent to those skilled in the art are accomtherefrom. An object of this invention is to plished by the present invention, one embodiment provide an improved machine forheat treating of which is illustrated in the accompanying articles constructed and arranged to insure the drawings in which: accurate locating of the operative parts relative Fig. 1 is a front elevation of a heat treating to each other and to a work piece during operamachine constructed in accordance with what tion. I now consider a preferred embodiment of this With certain articles it is desirable to treat, invention; as by heating and quenching to harden, spaced Fig. 2 is a side elevation thereof; areas on the article without treating the re- Fig. 3 is a top plan view thereof; maining or intervening areas. This is the case, Fig. 4 is a transverse sectional view on the for example, with such articles as airplane proline 4-4 of Fig. 2; peller hubs in which a hub having a central bore Fig. 5 is a section through a part of the mafor mounting upon a propeller shaft is provided chine on the line 5-5 of Fig. 1; with a plurality of symmetrically arranged, Fig 6 is a horizontal section on the line 6-6 radial, propeller-blade receiving sockets around of Fig. 1 showing the work holder and work piece the circumference'of' the hub. The inner surin plan;

face of each socket is hardened by heating and Fig '7 is a view showin the base member of quenching to increase its strength and wearing the work support in plan, parts being broken properties, but without hardening the outer wall away; I of any socket or the main body portion of the Figs. 8 and 9 are transverse sections on an hllbenlarged scale on the lines 8-8 and 9-9, re-

A further object is to provide a heat treating spectively, of Fig. 7 a machine constructed and arranged to treat Fig. 10 is a rear view of the work suporting spaced areas on a work piece such, for example, pedestal, partly in section, the view being taken as the spaced propeller-blade sockets of a proon the line Ill-l0 of Fig. 5, and showing a work pellerhub without affecting the physical properpiece in position; v ties and characteristics of the remainder of the 'Fig. 11 is a transverse sectional view of a dearticle. tail taken on the line lI--|I of Fig. 5

A still further object is to provide a machine 40 Fig. 12 is .a sectional view of the upper secfor heat treating a work piece constructed and tion of the quench nozzle supporting arbor and arranged to permit easy and accurate indexing associated mechanism, taken on the line I2l2 of a work piece between heating operations to of Fig. 2; and

successively present and accurately locate dif- Fig. 13 is a similar view of the quench nozzle ferent areas of a work piece for treatment. and heating head with the centering means A still further object is to provide a machine therefor, showing the same in operative heatfor hardening the inner faces of annular parts ing relation with a work piece, and taken on the by electromagnetic induction heating and line I 3-! 3 of Fig. 2. quenching, in which provision is made for ac- The particular embodimentof the present invention which has been chosen for illustration is especially adapted to harden, by electromagnetic induction heating and quenching, the inher surfaces of propeller-blade receiving sockets Q on an airplane propeller hub to a predetermined and controllable depth and pattern. However,

it will be apparent that the present invention is not limited to a machine for treating any specific article but, on the contrary, is equally adapted to machines for operating on various types of work.

The illustrated machine comprises an induction heating head and a work support which are relatively movable to move a work piece on the support into and out of induction heating relation with the head, and means is provided for rotating the work piece during the heating op ration. A work enclosing hood is supported for movement relative to the work piece and heating head and is adapted to engage the base of the work support during treatment so as to surround and enclose the work piece. The hood is rotatably supported on a yoke surrounding the head supporting arbor and the arbor is provided with a yoke engaging surface for accurately centering the head in the work piece when the hood is in operative position during the heating period. Primary and secondary quenching nozzles are incorporated in the hood construction for directing quenching fluid against the outer face of the work piece, either during or after the heating operation, or both, to prevent the adjacent area from becoming heated to any appreciable degree by conduction. An inner quenching nozzle is also provided for directing quenching fluid against the inner surface of the socket to harden the same after the heating operation. The work support is not only constructed and arranged to accurately and rigidly position a work piece in proper relation to the heating and quenching heads, but is provided also with mechanism permitting indexing of the work piece between heating operations to successively locate separate areas of the work piece in position for treatment.

The illustrated embodiment of the present invention is shown in connection with a frame 20 having a work holder mounted upon a work supporting spider 2| secured at opposite sides to cylinders 22 each of which is connected at each end to upper and lower bearing sleeves 23 and 24, respectively. The sleeves are slidably mounted on a pair of vertical guide rods 25 secured in brackets 25 on the front of the machine frame 20. Each cylinder 22 has an inner diameter greater than the outer diameter of the associated rod 25. Each guide rod has a piston head 21 located within the associated cylinder 22. Fluid pressure ports 28 and 2! connect fluid passages 3| and 32 extending through the rods 25 with the interior of the cylinders 22 on Opposite sides of the piston head 21. Suitable valve mechanism of any desired type, not shown, can be employed for delivering and exhausting fluid pressure to and from the cylinders 22 through the ports 28 and 29 for the purpose of raising and lowering the work supporting spider 2|, and the work support mounted thereon, in the manner hereinbefore described.

A work holder supporting plate 33 is supported on the spider 2| and has a central, vertically extending, annular flange 34, see Fig. 4, for rotatably supporting through bearings 35the vertical hollow shaft 35 of a rotary supporting member 51 to which is secured for rotation therewith a suitable work support.

The work su port comprises a base formed by a plurality of superimposed plates which are channeled to provide inlet passages for cool quenching fluid and an outlet for heated quenching fluid after it has been used. As illustrated in Figs. 4. 5, and '1 to 9, this base comprises a lower plate 35 secured to the rotary support 31; an intermediate annular plate I! having a central annular hub 4| and outer, circumferential rim 42, the annular rim being bolted to the lower plate I. as best shown in Fig. 5. It will be noted that the annular rim 42 is of less axial extent than the hub 4|, and that a ring 43 rests on the rim 42 and cooperates with the upper face of the hub 4| to provide a flat support for a top plate 44 on which is mounted a work holder pedestal 45. Suitable gaskets are preferably provided between the various lates of the work holder base. An annular ring or gasket 45, of rubber or the like, see Figs. 4, 8 and 9, is provided around the edge of the upper face of top plate 44, for a purpose to be hereinafter described.

As best shown in Figs. 5 and 8, the upper face of the lower plate 35 is channeled to provide quenching fluid delivery passages 41 beneath the plate 39 leading to a passage 49 in the rim 42 of the plate 39 in turn leading to a port 5| in the side of a tubular member projecting upwardly through the superimposed plates 32 and 44 and for a distance above the top plate 44, see Fig. 8. The tubular member 52 has a discharge port 53 communicating with a discharge outlet passage 54 formed in the ring 43 to permit quenching fluid remaining in the tubular member and associated parts at the end of a quenching operation to drain out. During quenching, the drain port 53 is closed by a valve 55 slidably mounted in the lower end of the tubular member 52 and having a head 55 subject to pressure of quenching fluid through a port 51 connecting the passageway 49 in the plate 35 with the end of the tubular member 52. It will be ap arent that the pressure of the quenching fluid during a quenching operation will be effective through the port 51 on the valve head 55 to raise the latter and close the drain port 55, at the same time bringing the port 55 in the side of the valve member 52 into registry with the port 5| communicating with the quench discharge passageway 49, thus permitting quenching fluid to flow upwardly through the tubular member 52. When the quench is cut ofl, release of the pressure allows the valve member 55 to drOp to the P ition illustrated in Fig. 8 in which the supply support port 5| is shut and a discharge port 5! opened to permit draining of the quenching fluid from the upper part of the tube 52 and the associated apparatus. It should be noted that the port 55 and the valve member 55 are so located with respect to the upper end of the valve that in moving upwardly the valve closes the outlet port 53 before the supply port 5| is opened.

The radially inner end of each channel 41 communicates through a port 5| with the hollow interior of the vertical hollow shaft 55 to which quenching fluid is supplied from a supply line 62 through supply passages 53 in a closure member 54 secured to the bottom of the spider 2|, port in a packing sleeve 55 and channel 51 between the sleeve 65 and the central tubular member 55, the channel 81 communicating, see Fig. 4, with the interior of the hollow shaft 55.

It will be seen from Fig. '1 that the radial channels 41 in the base of plate 38 alternate with somewhat similar channels 1| leading to passages 12 formed in the annular rim 42 of the plate 35 and corresponding to the previously described passages 48 in the same rim, with which the passages 12 alternate. Like the passages 45,

the passages 12 lead to vertically extending tubular members 13 through valve controlled ports edge coinciding with and similar to those described tubular members 52.

Unlike the channels 41, however, the inner ends. of the channels II open through ports I4 to the inner central opening 15 in the hub of the plate 39, this opening communicating with the interior of the tube 68 and being connected thereby to a quenching fluid supply line I6.

The work enclosing hood 7'! is mounted for rotation in a supporting spider 19, secured to the upper ends of three circumferentially spaced supporting rods I9 which extend downwardly through the worksupporting spider 2I into cylinders 8|, see Fig. 1, by means of which the rods 19 and hood H can be raisedand lowered through the medium of fluid pressure delivered to the lower end of the cylinders 8I through a supply line 82, a suitable valve, not shown, being employed to control the delivery and exhaust of fluid pressure to and from the cylinders i. Any suitable form of construction, not shown, can be employed to provide a fluid-tight joint between the hood supporting rod I1 and the inner walls of the cylinder BI, such as a conventional piston head or the like. The hood supporting spider I8 is also provided with extensions 99 slidably engaging the guide rods 25 to guide the movein connection with the ment of the spider and hood into and out of.

operative position as indicated in Fig. 1.

The hood is rotatably supported in the spider 18 by a hollow hanger 84 secured to the top of the hood and mounted for rotation in roller bearings or the like in the center of the spider 18. An oil chamber. 09 surrounds the bearing supporting flange 81 and a pump 00 circulates oil through the bearings.

Like the work supporting base above described, the top of the hood I1 is formed by a plurality of channeled plates and rings that are so combined as to provide passages for the delivery of quenching fluid to the outer face 01a work piece enclosed within the hood. As illustrated this is formed by a circular top plate 9| bolted to the lower end of the annular hanger 84 and having secured around a central opening 92 therein an upper nozzle ring 93 adapted to overlie the end of a work piece when the hood is in operative position, see Figs. 4 and 5. The ring 93 cooperates with 'a second, intermediate, nozzle ring 94 to form a primary quenching nozzle 95 for directing a quenching fluid on the outer edge or shoulder of an annular work piece such as the propeller blade socket 96 of the propeller hub 91 illustrated.

The intermediate nozzle ring 94 cooperates with a third, lower, nozzle ring 98 to form a secondary quenching nozzle 99 for delivering quenching fluid to an intermediate portion of the outer face of the work piece. The intermediate ring 94 is mounted on and secured to an annular plate IOI, in turn bolted to a lower plate I02 having an cry of the circular top plate 9|.

Quenching fluid is conducted to the primary quenching nozzle 95 through a passage I 09 form between the top plate 9| supporting plat IOI, see Fig. 5, which passageway opens through ports I04 near the outer edge of the lower plate I02 with depending hollow tubes I05 extending downwardly from the plate I02 to which they are secured within the hood 11. When the hood is located in operative engagement with the base of the work support, as illustrated in Fig. 5, .the lower end ofeach tube I05 fits over the upper end or the associated ver-.

secured to the periph- 4 standard 45 securely bolted and keyed to the suptically extending tubular member 19 in thework supporting base so that quenching fluid passing through the tubular member I3 flows upwardly through tubes I05, ports I04, passage I03, to the primary quench nozzle 95. Quenching fluid is supplied to the secondary quenching nozzle 99 through a circular passage I06 formed between the intermediate and lower nozzle rings 94 and 90, communicating through ports I0I' with an annular passage I09 formed in the ring I02 and connected by radial passages I09'in the ring I02 to a circumferential rowof ports III communicating with tubular quenching fluid delivery tubes II2 secured to and suspended from the plate I02 in a manner. similar to the primary quench' tubes I05 with which the secondary quench tubes II2 alternate circumferentially of the plate I02. The lower end of each secondary quench tube II2 fits over an associated tubu-.

lar member 52 at the work supporting base when the hood is in engagement with the base.

A work holder for directly supporting the work piece is mounted upon the work supporting base and is constructed and arranged to permit a work piece to be easily and quickly installed in place and to be rigidly held in exact, predetermined position during the treatment thereof. Indexing means is provided so that the work piece can be accurately indexed between successive heat treat ing operations to present different spaced areas of the work piece to the heating and quench heads.

As illustrated, the work holder comprises the porting base. A spindle H4 is. eccentrically mounted at one end in a rotary bushing I I5 having diametrically opposed slots IIO adapted to coopcrate with a removable key I" by means of which the bushing can be secured in either of two positions in a supporting collar I ill on the standam 45, to support the spindle at either of two levels, depending on the dimensions of the work piece being treated. A work supporting sleeve H9 is held on aspindle II4 by a key I2I and clamping nut I22. An adapter ring I23 is secured in a recessed. portion of the supporting sleeve II 9.

In the drawings the work piece is shown as aposition thereon by a beveled clamping disc I24 adapted to engage the beveled edge of the hub bore. The clamping disc is secured to a short shaft I25 rotatably mounted in the upper end of an arm I28 slidably and rotatably supported on a hollow shait I21 projecting outwardly from a supporting bracket I28. A hand wheel I29 is mounted on the outer end of the shaft I25. The opposite end of the shaft I25, adjacent to clamping disc I24, is recessed to receive the projecting end of the work supporting spindle II4, a pin I3I mounted in the recess 01' the shaft I25. being adapted to engage the bayonet slot I92 in the ad. and the nozzle ring' spindle. A detent mechanism I39 is provided for yieldingly holding the shaft I25 in proper work locating position. The lower end of the arm I20, below the supporting shaft I21 has a pair of feet I34 adapted to engage supporting surfapes I when the bracket arm I 26 is in operative work supporting position, see Fig. 5. To release a work piece the Wheel I29 is rotated to unlock the pin and bayonet slot connection permitting the arm to be moved bodily to the left along supporting shaft I21, see Fig. 5, to withdraw the clamping disc I24 from engagement with the bore ofthe propeller hub. This removes thcfeet I54 from engagement with the lupportlng surfaces I55, after which the arm can be tilted about the shaft I21 to the position shown in dotted lines in Pig. 4, in which position it is held by a rod I55 or the like engaging a suitable stop I51 on the side of the-bracket arm. This leaves the end of the work supporting spindle II4 free and the work piece readily accessible for removal therefrom.

Mechanism is provided'for accurately locating the work piece in proper position on the spindle and for indexing the work place between successive operations for presenting different blade sockets to the heating and quenching heads. This mechanism, as illustrated, comprises an indexing plate I35 secured to the work supporting bushing I I5. A pin I35 is secured in the plate in position to engage one of the bold openings I4I formed in the hub. The indexing plate is accurately held in position to properly locate a socket for treatment by an easily releasable locking mechanism such. for example, as a pin I42 slldably mounted in the edestal to engage an opening I43 in the index plate. The pin can be withdrawn by a lever I44 pivoted to the pedestal and connected at its lower end to a shaft I45 slidably mounted in a slotted bearing I45 and extending forwardly through the bore of the hollow shaft I21, a helical spring I41 normally pressing the shaft to hold the pin I42 in operative position.

It will be apparent that after the hardening operation, the work can be easily and'quickly, and at the same tim accurately indexed by releasin the locking pin I42 by pulling the shaft I45 to the left as indicated in Fig. 5, whereupon rotating the hand wheel I25 to the right will rotate the work supporting shaft I I4 and the hub supported thereon to bring an untreated socket into position for hardening.

During the heat treating operation the work holder and support, together with the surrounding hood and quench nozzles are rotated by a motor I48, see Fig. 4, and driving gear I45 mounted on the central hollow shaft 55, the motor casing being secured to the bottom of the spider MI. The gear I45 is also geared to an oil pump II which circulates lubricant from reservoir I52 through a feed tube I53 and passage I54 to the bearing 35. The passage I54 extends around the supporting plate I35 and an opening I55 is located above the gearing connecting the motor I45 and the gear I45 for the lubrication thereof.

A splash pan I55 is secured to the upper edge of the plate 33 for a purpose to be hereinafter described and a quenching fluid drain outlet I51 is provided in the bottom plate 55 for draining oi! quenching fluid. Drain openings I55 and I55 in the intermediate plate 55 and lower plate 55, respectively, and opening I55 in top plate 44 permit the quench fluid to flow into the outlet I51. The heating head I5I is shown as having a multi-tum, single, hollow conductor, inducing coil I52 surrounding the usual laminations I55 mounted on a coil support I54 between cooperating shoulders I55 formed on the support and. on a lamination holding ring I55 held in place by an annulus I51 and nut I58 threaded to the coil support I54. During heating the hollow coil is supplied with coolant through a supply pipe I55 connected to a supply passage I1I formed in the coil support leading to an annular passage I12 connected to the lower turn of the inducing coil. The opposite end of the coil extends upwardly through the annulus I51 into a channel formed in a split clamping yoke I14 to which is also connected the coolant discharge line I15.

The upper end of the coil support I54 is threaded to a collar I15 engaging a shoulder I11 formed on a sleeve I 15 threaded at its upper end to the lower end of an inner arbor member I15. It will be noted that the inner arbor member I15, sleeve I15, and coil support I54 are electrically connected together and to the lower turn of the induction heating coil I52. The upper end of the coil supporting member I54 is secured in the split clamping yoke I14 which is insulated from the coil supporting member by a ring I5I of electrical insulating material. The clamping yoke Is mounted at the lower end of a supporting hanger I52 suspended from a nut I55 threaded to the lower end of an outer, annular. current conducting arbor member I54 concentric with and surrounding the inner arbor member I15 and insulated therefrom by a sleeve I55 of electrical insulating material. It will also be noted that the outer arbor member I54, hanger I52 and clamping yoke I14 are electrically connected together and to the extension I15 of the induction heating coil.

The arbor members are supported from a transformer supporting frame I55 and are electrically connected in the usual way to transformer coils located within the transformer housing I51, the associated electrical apparatus being housed within the frame 25 01' the machine. It will be seen that the nut I55 and hanger I52 are insulated from the sleeve I15 by a collar I55 of electrical insulating material.

Surrounding the lower ends or the arbor members, and supported upon the nut I55, is a cylindrical member I55, the lower annular end of which engages a shoulder I5I on the outer arbor member I54 so that the cylindrical member is clamped between such shoulder and the nut I55. During the heating operation, when the heating head is positioned within the work piece socket. the outer surface of the cylindrical member I55 is slldably engaged by the circular wall of a central opening I52 in a centering collar I55, see Fig. 5, mounted within an annular plate I54 supported on the yoke 15 which supports the hood supporting hanger 54. An oil seal is provided for preventing oil flowing from the reservoir 55 to the interior of the hanger 54 by an annular oil seal plate I55 between which and the top plate I54 is an oil seal I55.

By engagement of the cylindrical member I55 with the surface I52 which is occasioned when the work piece, heating head and work enclosing hood are in operative heating position, as shown in Fig. 5, the heating head is rigidly held in exact position relative to the socket being treated and rotation of the parts occurs on an axial line which is rigidly located between the lower rotary work piece support 51 and shaft 55 which are accurately centered by the supporting spider and assoclated guide rods 25, and the upper center of rotation formed by the rotary hanger 54 which is accurately positioned by the hanger 15 and de rods 25.

Means are provided for quenching the inner, heated surface of the socket. As shown, a quench tube I51 is positioned within the inner annular arbor member I15 and is provided with nozzle openings I55 shown as arranged in circumferentinl rows at the lower end of the tube, see Fig.

15. The lower open end of the nozzle tube is Obviously. any speoiflc' closed by a plug I55.

construction of nozzle and arrangement of nozzle openings can be employed. I

The tube may be in a single piece or sectional. As shown it extends upwardly through the transformer housing 101, through a lower cylinder head 201, cylinder 202, upper cylinder head 203, quenching fluid supply chamber 204 and, when in its upper raised position illustrated in Figs. 12 and 13, projects into an annular, chambered flange 205, closed by a threaded plug 206. Quenching fluid which may be gaseous or liquid, but which in the illustrated machine is preferably air, is admitted to the supply chamber 204 through a port 205' connected to a supply line 206', see Figs. 1- and 13. When, the quenching nozzle andtube are in elevated, inoperative, nonquenching position, shown in Figs. 12 and 13, it will be apparent that the open upper end of the quench tube is out off from the supply chamber 204 by projecting into the chambered flange 205, but that upon lowering the tube to the operative quenching position shown in Fig. 4, the upper end of the tube will be withdrawn from the chambered flange into communication with the supply chamber 204 so that quenching fluid will flow freely through the quenching nozzle. The dimensions are such that a predetermined extent of downward movement sufllcient to locate the nozzle in a predetermined position is required before quenching fluid can flow. A piston 201 is secured to the nozzle tube and mounted within the cylinder 202. A fluid pressure line 208 is connected through a port 209 and passage 2| 1 with a restricted annular passage 212 opening at one end into the cylinder at one side of the piston which has an annular end 213 of reduced diameter adapted to enter an annular opening 214 of less cross sectional area than that of the main cylinder. The pressure-supply port 209 is also connected through a check valve 215 and passage 216 to the main part of the cylinder 202.

A second pressure line 211 is connected to a port 218 in the lower cylinder head 201, the port 219 communicating through a passage 219 with a restricted annular opening 221 at the lower end of the cylinder adapted to receive a lower extension 222 on the piston head 201. The port 210 also communicates through a check valve 223 and passage 224 with the main cylinder.

It will be readily understood that the upper port is at its lowermost position as shown in Figs. 1 and 2, and the work enclosing hood 11 is in raised position shown in dotted lines in Fig. 1, thus making the work holder easily accessible for the positioning of a work piece in place. With the work clamping mechanism on the arm 128 shifted to inoperative position, shown in dotted lines in Fig. 4, a work piece such as the illustrated propeller hub having three, spaced, blade receiving sockets 96, is positioned on the work holding spindle 114 so as to abut against the sleeve 115. spindle 114 is securely held in either of its two adjust d positions, the particular position depending upon the size of the work piece, the

, eccentric being secured in proper position by the and lower extensions 213 and 222, respectively,

on the piston head 201 cooperate with the restricted cylinder extensions 214 and 221, respectively, for cushioning the movement of the quench head at each end of its stroke, needle valves 225 being employed to control the degree of cushioning. Obviously, introduction of fluid through the port 209, when the piston 201 is in the upper position illustrated in Fig. 12, applies pressure to the upper ends of the extension 213. This starts the piston downwardly after which the full pressure is delivered thereto through'the check valve 215 and passage 216. The lower end of the stroke is cushioned by the annular extension 213 of the piston entering the reduced area 221 thus restricting the area for the-exhaust of fluid through the passage 210 and cushioning the lower end of the stroke. The reverse operation is similarly carried "out by applying pressure to the lower side of the piston through the port 210. It will, of course, be readily understood that the control of fluid pressure in the operating lines 200 and 211 is obtained through any suitable, conventionaL-valve mechanism.

In operation, at the beginning, the work supkey 111, Figs. 5 and 10. The sleeve 119 and adaptor 123 on which the work piece is directly supported are shaped and proportioned in accordance with the particular work to be treated. In positioning the work on the support, one of the perforations 141 in the propeller mounting flange is located over the pin 139 mounted on the indexing plate 130, so that the hub and indexing plate are rigidly connected together for simultaneous indexing movement. The indexing plate and hub are normally held against any movement on the spindle by the locking pin 142. When properly positioned on the support, the work piece is locked in place by returning the arm 126 to vertical position and sliding it toward the spindle 114, to the right in Fig. 5. Obviously, difierent positions of the work supporting spindle to accommodate different sizes of work pieces will require different lengths of arms 126. Bringing the arm 126 into a vertical position moves the supporting and centering disc 124 into engagement with the open bore of .the work piece, and the pin 131 is locked in the bayonet slot 132 by rotating the hand wheel 129 to the right, the parts being resiliently held in this position by the detent mechanism 133. In moving the arm I26 inwardly into work supporting position, the feet 134 are moved on to the supporting surfaces 135 which accurately locate the arm 126,

. the outer end of the work piece being thus rigidly and accurately positioned so that the socket 96 to be treated is also rigidly held in accurate position for such treatment. Accuracy in locating the work piece for treatment is required because of the close tolerances necessary between the work piece and the heating and quenching heads for the highest degree of perfection in the finished product.

With the work piece securely mounted on the support, the hood 11 is lowered from the elevated position shown in dotted lines in Fig. 1 to the lower position shown in solid lines in Figs. 1 and 2 in which it rests upon the base of the work support. When in this position the primary quench tubes 105, see Fig. 5, the lower ends of which are secured within an annular ring 231, fit over the tubular quench supply members 19 in the work supporting base for receiving quenching fluid therefrom and transmitting it' to the primary quench nozzle 95. In the same way the secondary quench tubes 112 fit over and receive quenching .fluid from the tubular members 52, transmitting such fluid to the secondary quench nozzle 99. The annular ring 231 snugly 1 The eccentrically supported work.

through the port 28.

piece on to the work supporting base and drains outwardly therefrom through drain openings 212, see Fig. 9, formed in the ring HI and top plate 44 and which communicate with drain outlets 233 formed in the upper face of the ring 43.

The downward movement oi the hood is occasioned iby exhausting fluid pressure from the cylinders 8| permitting the rods 10 to move down-- wardly under the weight of the hood and supporting yoke. With the hood in operative position, the work support is raised from the position shown in Figs. 1 and 2 to that illustrated in Fig. in which the socket 96 to be treated is raised into position around the heat head 2|, the latter being accurately centered with respect to the work piece by engagement of the cylindrical centering member I89 with the inner centering surface I92. This also accurately aligns the centers of rotation of the work piece, the work support, and the hood, with the center of the heat head. The work holder, hood, and work piece are rotated by the motor I48 and electric current of high frequency and high power is delivered to the coil of the heating head to inductively heat the inner, sinuous surface of the associated socket 9G by induced electromagnetic currents in the manner known to the art, the area penetrated by such currents being conflned to a predetermined depth and pattern. The outer wall of the socket 0B is maintained relatively cool, at a temperature substantially below any hardening temperature. For this purpose the quench controlling valves, not shown, are so manipulated that quenching fluid is delivered through the primary quenching nozzle against the upper shoulder and outer surface of the socket 96 during and after the heating period which may last in connection with the work piece illustrated for approximately 17 seconds. I have successfully treated work pieces of this type by applying the primary quench approximately 15 seconds after the start of the heating operation. At the end of the heating period, the work supporting fixture and associated hood 11 are lowered to the position shown in Figs. 1, 2 and 4 by admitting operating fluid to the cylinder 22 through the inlet valve 20, above the piston head 21 and exhausting fluid from beneath the head Substantially simultaneously with this movement, operating fluid is delivered to the quench nozzle operating cylinder 202 through the inlet port 200 to lower the piston head 201 and move the associated inner quench nozzle I91 downwardly so as to project below the heating head Iii into the heated sockets 06, as best shown in Fig. 4. As above described, it is necessary to move the quench tube and nozzle downwardly a distance sumcient to withdraw the upper end of the tube from the chambered flange 205 so as to insure the nozzle being lowered entirely away from the locating coil before fluid can flow. through the nozzle. When in this position secondary quenching fluid is delivered through the secondary quench nozzle 9!, and additional quenching fluid, which is preferably a gaseous medium such as air is directed against the heated sinuous surface by the nozzle I91 to quench such surface and harden it as well as a certain predetermined area, generally indicated in Fig. 4, which lies somewhat below the bottomsof the low portions of the sinuous surface. Preferably the quenching fluid delivered through the nozzles 80 and I0 is a liquid which flows down over the exterior of the work piece and is drained out through the base of the work support as above described.

Upon completion of the operation, fluid pressure is delivered to the lower end of the cylinder 202 to retract the inner quench nozzle to inoperative position within the heating head and to the cylinders 0| to raise the hood H to its upper position whereupon a work piece can be indexed to bring another socket 98 into position for treatment. In this operation the shaft I4! is pulled outwardly against the tension of the spring I41 to withdraw the locking pin I42 from engagement with the index plate I38. The hand wheel I20 can then be rotated to the right to bring a fresh untreated portion of the work piece, such as a socket 96 into proper position for treatment. Helease of the shaft I40 permits the spring I41 to shift the locking pin I42 into engagement with another opening I43 in the indexing plate.

Although I have described in detail one specific embodiment of a machinewhich is illustrative of the present invention, it will be apparent that the invention is not limited to such details, but that it can be variously modified and adapted within the scope of the present claims.

What is claimed is:

1. In an apparatus for heat treating metallic articles, a support, a heating head, an arbor carried by said support and secured at one end to said head, said head and said arbor for a large portion at least of its length being spaced from said support, said arbor having a guide portion thereon adjacent said head, a centering collar coaxially aligned with said head and arbor, means cooperabie with said support for supporting said collar for movement axially of said collar, means for moving said cooperable means, said collar upon movement of said cooperable means in one direction to a predetermined position being engageable with said guide portion to rigidly hold said arbor against lateral deflection and upon movement in the opposite direction to disengage said guide portion.

2. In an apparatus for heat treating metallic articles, a support, a heating head, an arbor carried by said support and secured at one end to said head, said head and said arbor for a large portion at least of its length being spaced from said support, Said arbor having a guide portion thereon adjacent said head, a centering collar coaxially aligned with said head and arbor, means cooperable with said support for supporting said collar for movement axially of said collar, means for moving said cooperable means, said collar upon movement of said cooperable means in one direction to a predetermined position being en gageable with said guide portion to rigidly hold said arbor against lateral deflection and upon movement in the opposite direction to disenga e said guide portion, the diameter of said guide portion and the internal diameter of said collar being sufflciently greater than said head to permit said collar to move longitudinally past said head.

3. In an apparatus for heat treating metallic articles, a support, an induction heating head having a helical winding thereon, an arbor carried by said supportand secured at one end to said head, said head and arbor for a large portion at least being spaced from said support, said arbor having a cylindrical guide portion thereon adi cent said head and of a diameter at least slightly greater than said head. said guide portion having a longitudinal recess in its circumferential face, a current conductor connected with said winding, said conductor extending parallel to said arbor and being disposed in said recess, a centering collar coaxially aligned with said head and arbor, means cooperable with said support and collar for moving said collar axially of said head and arbor, and means for moving said cooperabie means, said collar being movable over said head into engagement with said guide portion upon movement of said cooperable means in one direction to rigidly hold said arbor against lateral deflection and upon movement in the opposite di rection to disengage said guide portion.

4. In an apparatus for heat ,treating metallic articles, a support, a heating head, an arbor-carried by said support and secured at one end ,to

said head, said head and said arbor for a largev portion at least of its length being spaced from said support, said arbor having a guide portion thereon adJacent said head, a movable carriage having means thereon spaced longitudinally from tioned means into and out of engagement with said guide portion, said collar when engaged with said guide portion rigidly holding said arbor against lateral deflection.

5. In an apparatus for heat treating metallic articles, a support, a heating head, an arbor carried by said support and secured at one end to said head, said head and said arbor for a large portion at least of its length being spaced from said support, said arbor having a guide portion thereon adjacent said head, a carriage having means thereon spaced longitudinally from said head and arbor for supporting an article to be heated by said head, guide means on said support and parallel to said arbor and supporting said carriage for movement longitudinally of said arbor, means for moving said carriage, a centering collar, a collar support guided on said guide means for movement of said collar axially or said arbor, and actuating meanscarried by said carriage and connected with said collar support for effecting said movement of said collar support, said collar at a predetermined position oi! said carriage being movable into and out oi. en-

tion thereon adjacent said head, an annular guide collar axially aligned with said head, a

collar support rigidLv connected to said collar,

said collar support on the one hand and said head and arbor on the other hand being relatively axially movable to position said collar and guide portion into and out of, closely fitting engagement, and means for effecting said relative movement, said collar support being held against movement transversely of said arbor whereby in I the engaged position of said collar and guide portion to prevent transverse deflection of said arbor.

7. In an apparatus for heat treating articles having a bore, a main support, means on said support for supporting the article to be heat treated, an annular collar, a collar support rigidly secured to said collar and connected to said main support for holding said collar in axial alignment with the bore of the article and in spaced relation to the article as supported by said supporting means, a' heating head spaced from the article as supported and in axial alignment with the bore thereof, an arbor secured at one end to said head at the side opposite the article, said head and arbor for a portion of its length being spaced from said main support, said head having a cylindrical portion thereon adJacent to and of greater diameter than said head and said annular collar having an internal diameter such as to permit closely fitting engagement between said cylindrical portion and the bore of said collar, said supporting means on the one hand and said head and arbor on the other hand being relatively movable to position said head and bore intoand out of concentric heating relation, and means for effecting said relative movement, said collar in the concentric heating relation position of said head and bore being arranged to .move axially past said head into closely ,fltting relation around said cylindrical arbor portion to hold said arbor and head against lateral deflection.

. HOWARD E. SOMEB. 

